package FirstWork;

public class ErJInZHi {
    public static void main(String[] args) {
        int i = countEr(15);
        System.out.println(i);
    }
    public static int countEr(int n){
        int count=0;
        while(n!=0){
            if((n&1)==1){
                count++;
            }
            n=n>>1;
        }
        return count;
    }
}
